前端开发过程中,我们会经常遇到这样的情景:比如选中某个指标obj,将其加入到数组checkedArr中({id: 1234, name: 'zzz', ...}),但是在将其选中之前要校验该指标是否已经被选择. 以前的思路是:循环数组checkedArr,如果checkedArr[i].id===obj.id,则说明该指标已经在数组中了. 在ES6中,数组得到扩展,新增了find和findIndex两个方法,可以用到这个情境中:  find() 方法返回数组中满足提供的测试函数的第一个元素的值.…
Follow up for "Search in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why? Write a function to determine if a given target is in the array. 这道是之前那道Search in Rotated Sorted Array 在旋转有序数组…
 本文为大便一箩筐的原创内容,转载请注明出处,谢谢:http://www.cnblogs.com/dbylk/p/4032570.html 原题: Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find the minimum element. You may assume no duplica…
Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand. (i.e., [0,0,1,2,2,5,6] might become [2,5,6,0,0,1,2]). You are given a target value to search. If found in the array return true, otherwise return false. Ex…
题目链接:https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/#/description 给定一个已经排好序的数组,数组中元素存在重复,如果允许一个元素最多可出现两次,求出剔除重复元素(出现次数是两次以上的)后的数组的长度. For example, Given sorted array nums = [1,1,1,2,2,3], Your function should return length = 5,…
Given a sorted array nums, remove the duplicates in-place such that duplicates appeared at most twice and return the new length.Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memo…
Follow up for "Search in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why? Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4…
题目链接:https://leetcode.com/problems/search-in-rotated-sorted-array-ii/#/description   姊妹篇:http://www.cnblogs.com/zpfbuaa/p/6531773.html   给出一个循环有序数组,与其姊妹篇不同的是其中允许元素出现重复多次.给定一个数字target,查找该数字是否存在于该数组中.   姊妹篇中的解决方法是使用折半查找,通过判断nums[left]和nums[mid]以及nums[r…
题目链接: https://leetcode.com/problems/remove-duplicates-from-sorted-array/?tab=Description   从有序数组中移除重复数字,并且返回不重复数字的个数   遍历操作: 可以使用新的for循环 for (int n : nums){}   每次进行对比,并且更新第一个遇到不相等的元素的下标为i 对数组进行重新赋值操作   当数组长度大于1时,ans初值为1,当数组长度为0时,返回0   参考代码 :   packag…
替换某个字符串中的一个或若干个字串为数组中某些值 php本身有自带的函数,可以不用循环非常高效的实现其效果: 实例代码:   $phrase  = "You should eat fruits , vegetables, and fiber every day.";  $healthy = array("fruits", "vegetables", "fiber");  $yummy   = array("pizza…